My OMM Ultra was on its last legs, I'd restitched the bottle holder a few times, replaced various cords etc and it was starting to wear out. I've just gone through the process that Will has above and ended up with the Lowe Alpine - I'm fairly pleased with it but its not quite as stable as the OMM was, is quite a bit smaller and is wearing through a little on the back mesh after half a dozen runs. I find it a bit tight to get a full set of gear in - it will fit but bounced about quite a bit when full so I have usually had my cag outside the bag around my waist which improves things a lot.
Plus points - mesh pockets meaning you eat when you should instead of when you can be bothered. The provided bottle is good and if/when you lose it you can stick an ordinary bike bottle in to replace it.
Minus points- The gap between the pockets does mean you can get more gear in but pushes the bottle further out, away from your back which probably adds to the bounce.
But its £22 in Keswick as opposed to the asking price for the Inov8 of about £35 - Pete Blands had some of the old version of the Inov8 on offer on the van.